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A mirror of the official Linux kernel repository just in case
e7c1d1c9b2
The CRC-T10DIF algorithm produces a 16-bit CRC, and this is reflected in the folding coefficients, which are also only 16 bits wide. This means that the polynomial multiplications involving these coefficients can be performed using 8-bit long polynomial multiplication (8x8 -> 16) in only a few steps, and this is an instruction that is part of the base NEON ISA, which is all most real ARMv7 cores implement. (The 64-bit PMULL instruction is part of the crypto extensions, which are only implemented by 64-bit cores) The final reduction is a bit more involved, but we can delegate that to the generic CRC-T10DIF implementation after folding the entire input into a 16 byte vector. This results in a speedup of around 6.6x on Cortex-A72 running in 32-bit mode. On Cortex-A8 (BeagleBone White), the results are substantially better than that, but not sufficiently reproducible (with tcrypt) to quote a number here. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
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| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
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| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.